The jaboticaba (Myrciaria cauliflora (Mart.) O.Berg. (Myrtaceae)) is a small tree native to the Minas Gerais region near Rio de Janeiro in southern Brazil grown for the purple, grape-like fruits it produces. Traditionally, an astringent decoction of the sun-dried skins has been used as a treatment for hemoptysis, asthma, diarrhea, and gargled for chronic inflammation of the tonsils (1). The fruit is 3-4 cm in diameter with one to four large seeds, borne directly on the main trunks and branches of the plant, lending a distinctive appearance to the fruiting tree. The jaboticaba fruit has a thick, purple, astringent skin that covers a sweet, white, gelatinous flesh. Common in Brazilian markets, jaboticabas are largely eaten fresh. Jaboticaba's popularity has been likened to that of grapes in the US (2). The fresh fruit may begin to ferment 3 to 4 days after harvest, so it is often used to make jams, tarts, strong wines, and liqueurs.
In Brazil, the fruit of several species, namely M. jaboticaba (Vell.) O.Berg, M. tenella (DC.) O.Berg, and M. trunciflora O.Berg, share the same common name (1-3). The phytochemistry of these fruits has not been extensively reported in the literature. The jaboticaba (no species distinguished) has been reported to contain tannins (1). The presence of cyanidin 3-glucoside (Compound 3) in M. cauliflora has been reported (4). M. jaboticaba reportedly contains peonidin 3-glucoside and its aglycone (5), and the related camu-camu berry (M. dubia), an edible fruit known for its high levels of ascorbic acid, contains Compound 3 and delphinidin 3-glucoside (Compound 4) as its main pigments (6).
Depsides are phenolic compounds composed of two or more monocyclic aromatic units linked by an ester bond. They are most often found in lichens, but have also been isolated from higher plants, including species of the Ericaceae, Lamiaceae, and Papaveraceae (10, 11). They have not been previously reported in the Myrtaceae. Depsides have antibiotic, anti-HIV, and antiproliferative activity (12, 13). Depsides also act as inhibitors of prostaglandin biosynthesis and leukotriene B4 biosynthesis. Depsides are also potent non-steroidal anti-inflammatories (14).
The anthocyanins are a group of well-studied phenolic compounds with antioxidant, anti-inflammatory, antimutagenic, and cancer chemopreventative activities (21). In one study, it was shown that UVB-exposed HaCaT keratinocytes pretreated with Compound 3 were protected from UVB-induced inflammation, inhibiting NF-kB and AP-1 activation and IL-8 mRNA expression (22). Depsides from foods and botanicals are less well-studied than the anthocyanins, possibly as a result of their limited distribution in higher plants, and their ability to inhibit IL-8 production and cytotoxcity against colon cancer cells has not previously been reported.
The jaboticaba is rich in anthocyanins, phenolic acids, flavonoids, and contains depsides. Accordingly, it would be advantageous to provide, isolate, and characterize the active compound(s) responsible for the strong antiradical activity of the crude methanolic extracts of the jaboticaba. It would also be advantageous to provide bio-active compositions containing these bio-active compounds and methods of administering them.